Remote control installation



July 3, 1945. 1.. FENCKH REMOTE CONTROL INSTALLATION Filed July 5, 1941 7; if 1 t INVENTOR'.

2 AA-M Y z 75! 7 ATTORNEYS,

Patented July 3, 1945 REMOTE CONTROL INSTALLATION Leonhard Finckh, Geneva, Switzerland, assignor to Landis &Gyr, AG., Zug, Switzerland, a corporation of Switzerland Application July 5, 1941, Serial No. 401,237

In Switzerland July 5, 1940 2 Claims.

'of different frequency.

The main object of the invention consists in the provision of improved safety methods and of means to avoid incorrect operations caused by foreign or disturbing impulses.

According to the present invention the said object is attained by a remote control installation in which the carrying-out of a desired operation is made dependent on the simultaneous occurrence of two alternating currents of different frequency, whereby the performance of an operation is controlled by a current impulse of one of the said alternating currents and of a time interval in the sequence of impulses of the other alternating current.

In the accompanying drawing there is shown by way of example one constructional'iorm or embodiment of the invention on a remote control installation. I

Fig. 1 shows in a diagram the displacement of the impulses,

Fig. 2 illustrates the connections in a diagrammatical manner.

The installation shown comprises a sending station I and a receiving station II. The sendin station I comprises a relay arrangement consisting of a transmitter start key ST, a reset key RT, a relay A with make contacts a1, a2 and a break contact as, a relay B with a make contact In, and a condenser K and resistances W1, W2 to cause a time lag, a relay C with a break contact C1, and a relay B with a make contract d1. The contacts d3, d1 control circuits I, 2, which are connected with the transmitting line 3. One of said circuits is an open circuit and the other a closed circuit. In the circuit l are an alternating current generator Q1 of frequency f1 and a band filter X1. The circuit 2 comprises an alternating current generator Q2 of frequency f2, and a band filter X2;

The relay arrangement at the receiving station II comprises an open circuit relay E with a make contact e1, a closed circuit relay G with a make contact 91, a relay H with a change-over contact hl and two break contacts ha, ha, a relay J with a changeover contact ii, a make contact is and a condenser K. There is also a resistance W: to

produce a time-lag, a final relay K with a changeover contact 701 and a make contact k2, a relay L with a change over contact Z1 and a break contact Z2, a relay M with a change-over contact on and a make contact 1112, a condenser K2 and resistances W4, W5 to produce a time-lag, and a resetkey RTi, as well as a signalling device 0. The relays E and G are each connected through band filters Y1 and M2 respectively with the line 3.

The connection of the individual switching elements of the remote control installation shown appears directly from the drawing and need not be described in detail.

The installation shown in the drawing is ready for operation. The diagram of impulses, Figure 1, illustrates that for an operation to be carried out there is required an impulse of the open circuit current T1 of frequency f1 and at the same time an interval between the impulses of a permanent current T2 of frequency f2.

To start an operation, the key ST at the sending station L is pressed, thereby de-energizin relay A. By de-energizing relay A, the contacts a1, a2 are opened and the closing of circuit contact as is effected. By opening the contact (12 the relay C is tie-energized at once and, owing to the lagging condenser K and the resistances W1, W2, the de-energizing of the relay B occurs slowly. The contact 01 of the relay C will be closed at once and the contact 011 opened. The latter is closed again as soon as the contact In is opened corresponding to the retarded drop of relay B. Therefore, the flow of alternating current in the line 3 of the frequency f .is interrupted for a short time. When the relay A is de-energized, the contact as is closed and therewith alternating current of a frequency f1 passes to the receiver II at the moment of opening the key ST. By pressing the key ST an alternating current impulse of the frequency f1 will be transmitted and simultaneously the permanent alternating current of th frequency f2 will be interrupted for a short time interval.

When an alternating current impulse of the frequency f1 arrives at the receiver station II, the

relay E is energized and the contact (21 is closed. The interval in a sequ'ency of impulses of the current of the frequency f2 effects the de-energizing of the relay G. The contact or is opened and therewith the relay H de-energized. The changeover contact in is operated and the contacts In, ha are closed. By changing over the contact hi, the relay M will be slowly energized by the condenser K2 and the resistances W4, W5, and by closing contact hi the relay L will be quickly energized by means of the elements Z1, hz, RTl.

The relay L which has been energized moves the contact Z1 and Z2 respectively to make and break positions. The relay J is at the same time energized and changes-over the contact i1 and closes contact i2. The relay J is rapidly energized, but the circuit of the relay is then immediately interrupted by movement of contact 12 to break position. The relay J is not deenergized instantaneously, but slowly, due to the action of the condenser K1 and the resistance W3.

If during the time interval between two impulses of frequency f2, corresponding with the time delay action of the relay J, an impulse of the frequency I1 is received by the receiver, the relay H will be energized, thereby closing the circuit comprising contacts hl, i2, (21, hi, and relay K. The relay K is thus energized and its contact In changed over and the contact k2 closes the circuit for the device to be controlled.

The operation cannot be effected if the permanent current of the frequency I: does not arrive at the receiver II at the predetermined time. The alternating current of the frequency f2 arriving too late cannot close the circuit of the relay K as the contact hl has been switched in after the relay J has been de-energized.

It the sustained current of the frequency it does not arrive at the predetermined time, the relay M will change-over the contact m1 and the contact m2 will be closed. The action of the relay M is retarded owing to the condenser I02 and the resistances W4, W5 the time lag corresponds with the time interval of the impulses. The signalling device 0 is thereby energized to signal a disturbance.

By striking the keys RT, RTl at the end of a signalling operation all the elements return to their initial position shown in Figure 2 of the drawing in which the system is shown ready for operation.

What I claim is:

1. In a remote control apparatus, adapted for actuation by alternating current impulses of different frequencies, one a normally sustained current interrupted for a determined period to vary its action and the other a current produced during such period of interruption of the sustained current, a receiver including in combination a signal circuit, a pair of primary relays, one being normally energized by the sustained current impulses of one of the frequencies and deenergized during the period of interruption thereof and the other being normally deenergized and adapted to be energized by the impulses of the current 01 the other frequency, said signal circuit being normally open, and means for closing the signal circuit when the relays are respectively deenergized and energized in timed order governed by the interruption period, said means including a normally open circuit normally disconnected from the signal circuit, a contact operated when the second named primary relay is energized to partly close and render said normally open circuit operative when closed, and a system of circuits adapted to be energized when the first named primary relay is deener'gized and having controlling relays therein for closing the normally open circuit and connecting it with the signal circuit during a period of time governed by and corresponding to the time period of interruption of the sustained current impulses.

2. In a remote control apparatus, the combination of a transmitter provided with means for transmitting permanent current impulses of one frequency, means for interrupting the transmission of such impulses for a definite period of time, and means for transmitting current impulses of a different frequency during the time period of interruption of the first named frequency, and a. receiver having a signal means therein, means responsive to the first named current impulses for normally rendering the receiver inoperable to actuate the signal means, means responsive to the second named current impulses during the interruption period of the first named current impulses for setting the receiver into action to 0;:- erate the signal if a current impulse of the first named frequency is received before the end of the period of time from the inception of the interruption, and means for rendering the receiver inoperable to operate the signal means in the absence of and in the event that an impulse of the first frequency is not received within the given period of time from the inception of the interruption.

LEON HARD FINCKH. 

